He was imprisoned after the assassination of Bangabandhu Sheikh Mujibur Rahman in 1975. Later, he joined the Civil Services (Judiciary) in 1982. He was elected General Secretary of the Judicial Services Association in 1995.
Shahabuddin retired as a District and Sessions Judge in 2006, after serving in various positions for 25 years. He was the law ministry appointed coordinator in the Bangabandhu assassination case. He served ACC as commissioner from 2011 to 2016.